Sewing machine lubrication



Dec. 5, 1961 R. Ross 3,011,592

SEWING MACHINE LUBRICATION Filed Feb. 19, 1959 Roger Ross wnwrsss BY 2 ,ZTTORNEY United States Patent 3,011,592 SEWING MACHINE LUBRICATION Roger Ross, Rockaway, N .J assignor to The Singer Manufacturing Company, Elizabeth, NJ., a corporation of New Jersey Filed Feb. 19, 1959, Ser. No. 794,341 Claims. (Cl. 184-6) This invention relates to sewing machines having relatively moving parts requiring lubrication, and more particularly, to a lubricating device for controlling the flow of lubricant to the relatively moving parts during the operation of the sewing machine.

It is an object of this invention to provide an improved device for automatically delivering predetermined quantities of lubricant during operation of a sewing machine and for stopping the flow of lubricant when the sewing machine stops.

Another object of this invention is to provide a lubricant pumping device for a sewing machine which operates in response to the operational vibration of the sewing machine casing.

Still another object of this invention is to provide an improved lubricant pumping device which requires no physical connection with the sewing machine operating device and thus may be installed quickly and economically and can be added readily to existing sewing machines.

It is also an object of this invention to provide a compact lubricant pumping unit for a sewing machine which may be accommodated conveniently within the limited space available within a sewing machine casing.

With the above and additional objects and advantages in view as will hereinafter appear, this invention comprises the devices, combinations, and arrangements of parts hereinafter described and illustratedin the accompanying drawing of a preferred embodiment in which: 1 FIG. 1 represents a vertical crosssectional view of the bracket arm head portion of a sewing machine having a lubricant pumping device of this invention applied thereto,

FIG. 2 represents an enlarged top plan view of the lubricant pumping device as arranged in the sewing machine illustrated in FIG. 1 with the top cover plate removed, and

FIG. 3 represents an enlarged side-elevational view of the lubricant pumping unit of this invention.

Referring to FIG. 1 of the drawing, indicates a portion of a sewing machine casing fitted with an end cover plate 11 and a top cover plate 12 together providing a hollow sewing machine bracket arm head. Journaled in bearings 13 and 14 in the casing 10 is an arm shaft 15 fitted exteriorly of the casing with a hand wheel pulley 16 through which the sewing machine is beltdriven. By means of a sprocket wheel 17 fast on the arm shaft and a lug belt 18, various stitch forming instrumentalities beneath the bracket arm head (not shown) are actuated. Also fast on the arm shaft is a counterweight 20 in which is secured a hollow crank pin 21. Iournaled within the hollow crank pin is the shank 22 of a driving sleeve 23 for an oscillating needle thread takeup lever 24 which is journaled on a hollow fulcrum pin 25 fast in the sewing machine casing. Embracing the hollow crank pin 21 is a driving link 26 pivotally connected in turn to a stud 27 fast on a needle bar 28 for reciprocating the needle bar endwise in a needle bar gate 29. The needle bar gate is pivotally mounted in the machine casing on a rock shaft 30 journaled in bearings 31-31, which rock shaft may be oscillated by way of a rock arm 32 by mechanism not shown in the drawing for imparting swinging motion to the needle bar in addition to the endwise needle bar reciprocation.

The sewing machine casing above the arm shaft bushice 2 ing 13 is formed with a lubricant distributing sump 40 containing porous material such as felt or the like. A Wick 41 leading from the sump extends into the hollow fulcrum pin 25 to lubricate the pivoted take-up lever. A radial port 42 formed in the arm shaft bushing 13 and joining the sump 40 directs lubricant to thebearing surface of the bushing. Seepage of lubricant from the bushing port 42 finds its way into the hollow crank pin 21 to lubricate the shank of the take-up driving sleeve 23 and by way of radial openings 43 in the crank pin lubricates the needle bar driving link 26. Excess oil collected in a cavity 44 in the casing 10 is carried by a wick 45 to the. bearings Iii-3i for the needle bar gate rock shaft.

As illustrated in FIG. 1, this invention provides a lubricant controlling device for metering lubricant to the distributional sump 49 in accordance with the lubrication requirements or" the above described relatively moving parts of the sewing machine. The sewing machine casing adjacent to the sump at is formed with a lubricant reservoir 59, however, the reservoir may be formed as a separate container secured to the machine casing. An oil hole 51 in the top cover plate 12 may be used to replenish the supply of lubricant in the reservoir'periodically,

Secured to the sewing machine casing adjacent to the reservoir 59 by screws 52 is a bracket 53 to which is fastened by screws 54 a leaf spring 55 extending substantialiy horizontally, but for an upturned loop portion 56. As illustrated in FIG. 2, the loop portion 56 is slightly narrower than the remainder of the spring and an enlargement 57 is formed in the spring adjacent to the loop all for the purpose of encouraging flexibility in the spring, particularly at the loop portion and providing for move ment of the spring in oscillation about a substantially horizontal axis near the loop when the equilibrium of the spring is disturbed.

At the free extremity, the spring 55 is disposed in a slot 58 formed in a movable member 59. The free end of the spring is slotted as at fill adjustably to accommodate a fastening screw 61 threaded into the movable member 59. The member 59 provides a weight supported by the spring 55 which vibrates in response to operational vibration of the sewing machine. By virtue of sympathetic vibrations occurring in the member 59 and spring 55 arrangement, the amplitude of motion of the member 59 can develop to a higher magnitude than that of the operational vibration in the machine casing from which the vibration of the block 59 is derived.

The member 59 is disposed partly submerged in luoicant in the reservoir 50 as illustrated in FIG. 1, and when vibrated during operation of the sewing machine, the movable member in oscillating about a substantially horizontal axis will raise and lower to a greater or lesser .extent into the lubricant, and, therefore, on each upstroke, will raise a film of lubricant adhering thereto.

A stationary block 62 is fixedly secured by a fastening screw 63 to the bracket 53 and extends contiguous to the movable member 59. The top surface 64 of the stationary block 62 is inclined downwardly from the side contiguous to the movable member 59 toward the bracket 53 to provide a conduit for directing lubricant from the movable member 59 to a wick 65 secured in a cavity 66 in'the top of the stationary block. The wick is directed to the sump 49 and excess lubricant not carried to the sump by the wick 65 will drain immediately back into the reservoir 50.

In order to increase the efficiency of the device as a lubricant pump, the free extremity of the movable member 59 is formed with a surface that is substantially vertical when the movable member is at rest. In the preferred embodiment illustrated in the drawing, this surface comprises two planar faces '76 arranged at an angle, to-

gether defining a wedge-shaped free extremity of the movable member. The stationary block 63 is similarly formed with a wedge-shaped notch congruous and contiguous to the free extremity of the movable member and defined by two planar surfaces 71 each disposed substantially vertically.

When the movable member is at rest'or at the midpoint of vibratiomthe surfaces 70, '71 will be disposed substantially parallel or equidistant from each other at all points. During vibration, the movable member in oscillating about a horizontal axis located in the vicinity of the loop 56 will partake of slight angular displacement and the surface 70 will move out of parallelism withthe surface 71. When the movable member swings downwardly, the lower portion of the surface/70 which is immersed in lubricant will move away from the surface 71 to admit an additional quantity of lubricant therebetween. On the upstroke, however, the lower portion of the surface 70 will move toward the surface 71 thus compressing the lubricant therebetween. Since on the upstroke, the upper portion of the surface 79 will, by the same token, move away from the surface 71, a portion of the lubricant compressed between the surface 71 of the stationary block 62 and the lower portion of the surface 70 will be urged upwardly to overflow down the conduit 64 to the wick 65.

This invention thus provides a lubricant controlling device for a sewing machine which is a durable compact unit operably by Way of normal operational vibration of the machine upon merely being secured to the sewing machine casing.

Having thus described the nature ofthe invention, what i I claim herein is: V

l. A lubricating device for a sewing machine comprising, a lubricant reservoir carried in said sewing machine, a movable member disposed partially submerged in lubricant in said reservoir, resilient support means for said movable member constraining said member for sympathetic vibration in a substantially vertical path in response to operational vibration of said sewing machine, lubricant conducting means for delivering lubricant within said sewing machine, and means fixedly positioning one extremity of said lubricant conducting means adjacent to said movable member and at a point above the lubricant level in said reservoir.

2. A lubricant pump adapted to deliver lubricant during operation of a sewing machine comprising, a movable member, resilient supporting means for said movable member means for securing said resilient suporting means relatively to said sewing machine with said member disposed partially submerged in lubricant and arranged for sympathetic vibration in a vertical path in response to operational vibration of said sewing machine, a lubricant receiving member, means for fixedly supporting said lubricant receiving member relatively to said sewing machine and closely adjacent to the path of motion of said movable member, and lubricant conducting means carried by said lubricant receiving member for directing lubricant from said movable member at a point above the level of said lubricant in which said movable member is disposed partially submerged.

' 3. For use with a sewing machine having a casing and a lubricant reservoir carried in said casing, a lubricant pump unit adapted to deliver lubricant from said reservoir during operation of said sewing machine comprising, a rigid bracket adapted to be secured to said sewing machine casing adjacent to said lubricant reservoir, a spring, means securing said spring to said bracket for flexing in a substantially vertical direction when said bracket is secured to said sewing machine casing, a weight secured to the free extremity of said spring, said weight being formed with a surface disposed substantially vertical and partially submerged in lubricant in said reservoir when said bracket is secured to said sewing machine casing, a lubricant receiving member fixed on said bracket, said lubricant receiving member being formed with a surface substantially parallel and contiguous to the surface on said spring supported weight, lubricant conducting means carried on said lubricant receiving member for distributing lubricant within said sewing machine casing, and a conduit formed on said lubricant receiving member from said lubricant conducting means to a point on said contiguous surface above the level of lubricant in said reservoir.

4. A lubricating device for a sewing machine having a casing and a lubricant reservoir carried in said casing comprising, a movable member disposed partially submerged in lubricant in said reservoir, 2. leaf spring secured to said sewing machine casing and to said movable member supporting said member for oscillation about a substantially horizontal axis, said movable member being formed with a surface disposed substantially vertically in the at rest position of said movable member, a lubricant receiving member, means fixedly securing said lubricant receiving member relatively to said sewing machine casing, said lubricant receiving member being formed with a substantially vertical surface disposed closely adjacent to and evenly spaced from the surface of said movable member in the at rest position of said movable member, and lubricant conducting means associated with said lubricant receiving member and extending to said substantially vertical surface thereon at a point above the level of lubricant in said reservoir for distributing lubricant within said sewing machine casing.

5. For use with a sewing machine having a casing and a lubricant reservoir carried in said casing, a lubricant pump unit adapted to deliver lubricant from said reservoir during operation of said sewing machine comprising, a rigid bracket adapted to be secured to said sewing machine casing adjacent to said lubricant reservoir, a leaf spring secured to said bracket for flexing about a substantially horizontal axis when said bracket is secured to said sewing machine casing, a movable member secured to said leaf spring for sympathetic vibration therewith in response to operational vibration of said sewing machine and disposed partially submerged in lubricant in said reservoir when said bracket is secured to said sewing machine casing, said movable member being formed with a wedge-shaped free extremity defined by a pair of planar surfaces each disposed substantially vertically in the at rest position of said member, a lubricant receiving member fixed on said bracket, said lubricant receiving memher being formed with a wedge-shaped notch congruent with and contiguous to the free extremity of'said movable member and defined by a pair of planar surfaces each disposed substantially vertically when said bracket is secured to said sewing machine, a conduit formed on said lubricant receiving member opening on said wedge-shaped notch at a point above the level of lubricant in said reservoir and sloping downwardly therefrom, and means for distributing lubricant from said conduit within said sewing machine casing.

Moore Oct. 29, 1940 Parry et al. Nov. 27, 1956 

